This study will enroll couples who are new or returning CrM users and who are trying to avoid a pregnancy at the time they begin use of the CrM. The participants will be recruited from CrM FertilityCare Centers. The design is a prospective cohort study, which is the optimal study design to assess different measures of effectiveness and intendedness simultaneously in a group of NFP users. Several of the key measures of intention and behavior required for this study must be assessed prior to the outcome of actual use of CrM over time and the outcome of pregnancy, to avoid recall bias. Outcomes for this study require relatively precise assessment of the timing of both intentions and behaviors, which is simply unavailable from recall. We plan to enroll at least 300 and up to 400 couples in the study. This represents 60% (300/497) of the estimated available and eligible couples learning the CrM for use to avoid pregnancy in one year at the participating FertilityCare Centers.